htcacheclean: Teach htcacheclean to limit cache size by number of

inodes in addition to size of files. Prevents a cache disk from
running out of space when many small files are cached.

Move the directory delete process to the "purge" section, so that
inode counts are accurate when querying for stats only.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1022230 13f79535-47bb-0310-9956-ffa450edef68